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Full text of "The Cambridge Natural History"

232

POSITION OF D1NOTHERIUM

their small size enabling them to be accommodated in the ja^
together. The skull of Dinotherium is lower than that of JSlepJia
or Mastodon. The bones of the skeleton generally are like thos
of JSlephiOS.

Though a suggestion of marsupial bones attached to the pelvi
has been discredited, there is no doubt that Dinotherium oceupie
the most primitive position among the Proboscidea; but at tlb
same time it cannot be regarded as the ancestor of Elephants, a
it is so much specialised in various ways. The incisors for oni
thing forbid this way of looking at the creature. It is an ancien
genus found in beds of Miocene age in Europe and Asia. It i
not known from America. The creature was larger than an;
Elephant. Eighteen feet in length has been assigned to it. Th<
enormous weight of the lower jaw and tusks seems to argue tha
it was at least partially aquatic in habit, and that it may hav<
used these tusks for grubbing up aquatic roots or for mooring
itself to the bank. At first there were naturalists who considerec
it as an ally of the Manatee, and the skull is not unsuggestive o
that of the Sirenia.

PyrotJiGrium has been referred to the Proboscidea ; but oui
knowledge of that form is limited to a few teeth from Patagoniai
rocks of an uncertain age.1 They are simple bilophodont molars
very like those of Dinotherium. A tusk has been found in tht
neighbourhood of these teeth which may possibly belong to the
same animal; but it is uncertain.

SUB-OKDER  7.    HYRACOEDEA.
This group of small mammals contains only one well-marked
genus which is usually named Hyrax, although Procama seems tc
be the accurate term. Popularly these creatures are known as
Coneys. They have a singular resemblance to Hodents, the short
ears and much reduced tail, besides the squatting attitude adopted
eonfecibuting to this merely skin-deep likeness. They agree witt
other Ungulates in the structure of the molar teeth, which are
mucti like those of Rhinoceros ; in the absence of a clavicle ; in
tfce absence of an acromion; in the reduction of the digits of the
limbs to four digits in the manus and three in the pes. On the
1 I*ydefcker, <dn* Mug. Za Plata, Pal. Argt iii. 1894.